A fucktard is a retard but even more fucked up. Being a retard means being stupid but being a fucktard is even worse because adding fuck to anything makes it 1000 times more offensive. Don't call someone a fucktard unless the are one because non-idiots can actually process what your saying. Also, only fucktards would look up words on urban dictionary so waddup fuckers.
When a teenager with ridiculously poor grammar submits a stupid and incorrect definition on Urban dictionary because they heard a term at school that's been around for decades, yet they believe they are one of the first people to hear it, and/or know the "real" meaning of it.
Dirty Sanchez is when a guy sticks his finger up a girl's anus and then wipes there finger on the girls lip. I know this b/c my hoars at my high school think I a fucktard.